The instant invention relates to container closures, and more particularly to squeeze-type container dispensing closures.
There are two major trends occurring in the design of dispensing containers and closures. The first trend is a focus on providing a “clean pour” during dispensing of the product. Many food products, such as mustard and ketchup have a high viscosity and require the user to both tip and squeeze the container to dispense the product. Past dispensing closures tended to leak product onto the top deck of the closure after dispensing, creating a messy appearance and often requiring cleaning to reseal the closure. The current emphasis in “clean pour” design is on creating a “suck-back” effect as pressure is released from the container to draw the product back into the closure.
A second trend is a growing number of dispensing containers and closures being designed so that they can be stored in an inverted position, i.e. cap down. In this regard, the product is always located right at the dispensing closure for easy dispensing right from storage. This reduces the need to tip and shake the container to push the product down to the dispensing closure. There is a balance however, between having the product at the closure for dispensing and the need to prevent the product from immediately spurting out once the lid of the closure is opened.
Both of these trends have resulted in the design of dispensing closures having various types of flexible valves that facilitate both a clean pour and inverted storage. For example, a silicone valve structure is illustrated and described in U.S. Pat. No. 5,271,531. While these silicone valves have been widely accepted by both the manufacturers and the consumers, they are somewhat more difficult to manufacture, as they require several inter-fitting parts, and thus they tend to be more expensive than traditional one-piece dispensing closures.
Another perceived drawback to the silicone valve closures is that they are constructed out of two different types of plastic and thus, from a recycling standpoint, they are more difficult to recycle because the silicone valve must be separated from the plastic closure body for recycling. While this is not a major issue in the United States, at least yet, it is currently a major issue in Europe where recycling is extremely important and even mandated in some countries.
Accordingly, there is a need in the industry for a one-piece dispensing closure that provides both a “clean pour” and the ability to store the product in an inverted position without allowing the product to leak out prior to squeezing the container. In addition, there is a need for a dispensing closure with an obstructed flow profile or a dispensing closure with a center channel and helical flow profile.
Finally, there is a perceived need for a single-piece disclosure constructed from one type of plastic so that it can be easily recycled.